Statutes are most easily located by citation, whether to public law number, session law number or the United States Code.
For a session law of Congress the official source is the Statutes at Large, the citation format for which is: Volume no. Stat. Page no., e.g., 104 Stat. 327.
An official citation to a Congressional session law also includes a public law number specifying its place in the chronological order of passage among the statutes of the Congress that enacted it, e.g., Pub. L. No. 101-336 - the 336th Public Law enacted by the 101st Congress.
United States Code citations (to whatever source - U.S.C., U.S.C.A. or U.S.C.S.) are specified by title, abbreviated code name and section number; e.g., 20 U.S.C. 1080 is a citation to Title 20 (Education), § 1080 of the official U.S. Code.
For state code citation methods, consult Table 1 of the Bluebook.
Dodd-Frank Wall Street Reform and Consumer Protection Act, Pub. L. No. 111-203, § 929-Z, 124 Stat. 1376, 1871 (2010) (codified at ) [Bluebook R. 12.4]
Statute Classification Tables
Sometimes search for a particular statute begins with an incomplete citation or a specific section or other subdivision of a law that could be a reference to a part of that statute either in terms of its slip and session law divisional organization or in terms of the location in the code in which it has been classified by subject.
Statute classification tables list in session law citation order and section-by-section sequence correspondences between the parts of a session law and the places in the code where they have been incorporated, either as new sections or as amendments to existing ones.
For the federal code, use the U.S. Code Classification Tables.
Ask yourself the following:
Google & Wikipedia
Statutes are often referred to by common names such as the Patriot Act or Family Medical Leave Act. A quick way to find a citation to a well known statute is to use Google and Wikipedia. Wikipedia entries often contain citation to both the public law number and U.S.C., and offer links to Congress.gov and GPO's FDSys (government sources for statutory docs).
Popular Name Tables
Government and commercial publishers of the U.S. Code have alphabetically arranged popular name tables. Popular names are generally based on an official name designation at the very beginning of a slip law, typically a "short title" that is part of the full citation to an individual statute. Each name is followed by Public Law and Statutes at Large citations and at least a partial list of the Code titles and sections to which the statute has been classified.
Use secondary sources (treatises, practice guides, law review articles, etc.) to learn more about the law governed by a particular statute or to learn more about the statute itself.
Use the subject index for the code in your jurisdiction. Indexes are found at the end of the print set; most indexes are multi-volume (even online). Westlaw contains indexes for the U.S. Code and for state statutes. LexisNexis does not.
When using an index, start with specific terms and proceed to more general terms. Use synonyms and alternative expressions (for example, "insolvency" as well as "bankruptcy"). Be creative and persistent but remember: not all legal issues are governed by statute. Go back to secondary sources if you fail to find an appropriate statute.
Most current statutes are easily found online. When keyword searching, try to anticipate the language used by the legislature in writing the law. It may be useful to start with a Wikipedia entry that discusses a particular legal topic to get key search terms. You may also want to search the index (if available) to get synonyms for key terms - and citations to potentially relevant statutes.